Various embodiments of the invention relate to a digital photographing apparatus.
In digital photographing apparatuses, such as cameras and camcorders, to capture a clear still image or a clear moving picture, it is necessary to correctly focus on a subject. Contrast auto focus (AF) method and phase difference AF method are AF adjusting methods for automatically performing focus adjustment. In general, the contrast AF method is used in a mirrorless camera or a compact camera and the phase difference AF method is used in a single-lens reflex (SLR) camera.
The contrast AF method is a method of acquiring contrast values with respect to image signals generated from an image pickup sensor while photographing by changing a position of a focus lens, and driving the focus lens to a focus lens position of a peak contrast value.
The phase difference AF method further uses a sensing device in addition to an image pickup sensor and detects a focus position from a phase difference of light received by the sensing device.
In a conventional phase difference AF method, a mirror is retracted during continuous photography, and light is not incident on a phase difference AF sensor for a long time during the retraction of the mirror. Thus, AF cannot be correctly performed and a target picture can be out of focus. In addition, if a pellicle mirror is used in a phase difference AF method, it is not necessary to retract the pellicle mirror, but high-speed continuous photography including AF is not performed in consideration of timing for controlling an iris or a shutter. In addition, the high-speed continuous photography is performed only when a position of an iris is fixed, and thus, photography cannot be performed by using a necessary iris value or aperture value. Since only an image that is completely captured is displayed during continuous photography, it is difficult to photograph a subject that is moving in real time.